Psilocybin has emerged as a promising therapeutic agent for psychiatric disorders characterised by cognitive rigidity and disrupted reward processing, including anorexia nervosa. While its pro-cognitive effects have been mechanistically probed almost exclusively through serotonin receptor subtype antagonism, the downstream contributions of dopaminergic syste...
Major depressive disorder (MDD) continues to pose a major therapeutic challenge due to its clinical heterogeneity. This chapter looks at the development of antidepressant treatments, starting with early interventions such as electroconvulsive therapy (ECT), monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs). Although these treatments t...
BACKGROUND AND AIMS: Drug discrimination procedures have made important contributions to the pre-clinical investigation of psychedelic drugs, such as psilocybin, lysergic acid diethylamide (LSD), N,N-dimethyltryptamine (DMT) and 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT). One of the most important being to highlight the critical role of central 5-HT2A rece...
Introduction Since the last edition of the Black Book, several innovative agents have been approved or are poised to be approved in the coming year. These include novel antidepressants, the first muscarine agonist for the treatment of schizophrenia, the first psychedelic which may be approved for the treatment of PTSD (Post Traumatic Stress Disorder), and th...
ABSTRACT A variety of classic psychedelics and MDMA have been shown to enhance fear extinction in rodent models. This has translational significance because a standard treatment for posttraumatic stress disorder (PTSD) is prolonged exposure therapy. However, few studies have investigated psilocybin’s potential effect in fear learning paradigms. More specific...
Psilocybin has shown promise for alleviating symptoms of depression and is currently in clinical trials for the treatment of anorexia nervosa (AN), a condition that is characterised by persistent cognitive inflexibility. Considering that enhanced cognitive flexibility after psilocybin treatment is reported to occur in individuals with depression, it is plaus...
Psilocybin has shown promise for alleviating symptoms of depression and is currently in clinical trials for the treatment of anorexia nervosa (AN), a condition that is characterised by persistent cognitive inflexibility. Considering that enhanced cognitive flexibility after psilocybin treatment is reported to occur in individuals with depression, it is plaus...
Major depressive disorder (MDD) is a chronic relapsing psychiatric disorder. Conventional antidepressants usually require several weeks of continuous administration to exert clinically significant therapeutic effects, while about two-thirds of the patients are prone to relapse of symptoms or are completely ineffective in antidepressant treatment. The recent ...
IntroductionMajor depressive disorder remains a prevalent world-wide health problem. Currently available antidepressant medications take weeks of dosing, do not produce antidepressant response in all patients, and have undesirable ancillary effects.Areas coveredThe present opinion piece focuses on the major inroads to the creation of new antidepressants. The...
BackgroundClinical studies suggest that psychedelics exert robust therapeutic benefits in a number of psychiatric conditions including substance use disorder. Preclinical studies focused on safety and efficacy of these compounds are necessary to determine the full range of psychedelics' effects.ObjectivesThe present study explores the behavioral pharmacology...
Hallucinogens constitute a unique class of substances that cause changes in the user's thoughts, perceptions, and mood through various mechanisms of action. Although the serotonergic hallucinogens such as lysergic acid diethylamide, psilocybin, and N,N-dimethyltryptamine have been termed the classical hallucinogens, many hallucinogens elicit their actions th...
Hallucinogenic drugs, such as lysergic acid diethylamide (LSD), mescaline and psilocybin, alter perception and cognitive processes. All hallucinogenic drugs have in common a high affinity for the serotonin 5-HT(2A) receptor. Metabotropic glutamate 2/3 (mGlu2/3) receptor ligands show efficacy in modulating the cellular and behavioral responses induced by hall...
N,N-dipropyltryptamine (DPT) is a synthetic tryptamine hallucinogen which has been used psychotherapeutically in humans, but has been studied preclinically only rarely. In the present studies, DPT was tested in a drug-elicited head-twitch assay in mice, and in rats trained to discriminate lysergic acid diethylamide (LSD), N,N-dimethyl-4-phosphoryloxytryptami...
It has been observed that agents with agonist activity at 5-HT2A receptors prevent neurotoxicity induced by the non-competitive NMDA antagonist, dizocilpine (MK-801). Subsequent behavioral studies reported complete antagonism by LSD and DOM of the stimulus effects of the related NMDA antagonist, phencyclidine [PCP]. The present study sought to extend those o...
Although psilocybin has been trained in the rat as a discriminative stimulus, little is known of the pharmacological receptors essential for stimulus control. In the present investigation rats were trained with psilocybin and tests were then conducted employing a series of other hallucinogens and presumed antagonists. An intermediate degree of antagonism of ...
This study investigated possible interactions between alcohol and hallucinogens in 22 lysergic acid diethylamide (LSD) and/or psilocybin users through retrospective structured interviews. Of those who had used LSD with alcohol, 86;7 per cent reported a complete blockade of subjective alcohol effects, while the remaining cases reported a diminished response. ...
Psilocybin, an indoleamine hallucinogen, produces a psychosis-like syndrome in humans that resembles first episodes of schizophrenia. In healthy human volunteers, the psychotomimetic effects of psilocybin were blocked dose-dependently by the serotonin-2A antagonist ketanserin or the atypical antipsychotic risperidone, but were increased by the dopamine antag...
In order to further evaluate the extent to which particular 5-HT receptor subtypes (5-HT1, 5-HT2) might be involved in the behavioral effects of hallucinogenic drugs, rats were trained to discriminate mescaline (10 mg/kg i.p.) from saline and were given substitution (generalization) and combination (antagonism) tests with putatively selective serotonergic an...
